1. Field of the Invention
Applicant's invention relates to a submersible pump drop pipe and casing assembly connection and method of manufacture for use in water well and related systems.
2. Background Information
In water well systems, a casing is inserted into the well to maintain the structure of the well. Within the well is placed a submersible pump to which is attached a drop pipe which carries the water from within the well to the surface. It is important in this system that the drop pipe not leak. Therefore, in modern practice pipes are joined together with couplings and sealed with large amounts of either cement or “pipe dope” to prevent leaking. The positioning of the couplings can take a great deal of effort to do properly. In addition, pipe “dope” and cement have long curing times which makes what should be a relatively short job incredibly time consuming. Unfortunately, with current practices and materials, well drillers do not have the ability to run the pipes into the well by simply and rapidly screwing one pipe into another.
Surprisingly, the present invention allows the driller to run one pipe into the well, align and screw in the next pipe, and continue until complete. No couplings are necessary. The pipes of the present invention do not require the use of large amounts of cements or pipe “dope” to obtain the water tight seal, only small amounts of threading compound need be used to ensure there is no accidental disconnection of the pipes in the future and to allow for the pipes to be easily disconnected in the future should the occasion arise. In addition, the driller does not spend time cleaning the pipe and threads of excess compound if maintenance must be made of the well pipes.
Of interest is that maintenance of well pipes can often create more problems than may have existed simply due to the design of current pipes. Existing pipe designs lack a significant degree of lateral strength such that if a section of pipe must be unscrewed and removed, the force needed to overcome the strength of the bonding agent can sheer the pipe and strip the threads. It is noteworthy; however, that the invention of the present application has a high degree of lateral strength. It was found that it takes 5,000 pounds of pull on a 2 inch pipe to break the pipe. In addition, it was found that laterally pushing on the pipe, a force of 1,000 pounds has to be exerted before the pipe will start leaking.
More specifically, the present invention utilizes two pipes for either the drop pipe or casing. When the two pipes are connected together a specially configured first cylinder section on the first pipe is used to align and direct the male threaded end of the second pipe into the first pipe to the second cylinder section which is also threaded. The two pipes are then screwed together. The water tight seal is formed by screwing the two ends of pipe together. In addition, because the first cylinder section extends out for approximately one inch, any lateral forces on the connection are exerted against the first cylinder section instead of on the second cylinder section, which is threaded. This gives lateral strength to the pipe.